The present invention relates to medical imaging of the heart, and more particularly, to automatic detection of aortic valve landmarks in medical images of the heart.
Aortic valve disease is the most common valvular disease in developed countries, affecting up to 1.8% of the global population. A damaged aortic valve may be remedied by implantation of an artificial aortic valve. During transcatheter valve implantation surgery, in which implantation of an artificial aortic valve occurs, 2D fluoroscopic images are captured in real time by a C-arm system to provide guidance to physicians performing the implantation. The aortic root structure is distinguishable from its background for only a short period of time after a contrast agent is applied. However, contrast agents are typically toxic and it is preferable that contrast agent usage be minimal.
Additionally, an image of the aortic root must be properly aligned within an image plane to provide a physician with maximum visibility to ensure proper implantation of an aortic valve. The centerline of an aortic root should be perpendicular to the normal of the imaging plane. The aortic root needs to rotate around this centerline properly in order to ensure that two coronary ostia appear well separated on fluoroscopic images because the coronary ostias can be used to provide guidance to physicians to ensure proper implantation of an aortic valve. Currently, physicians need to apply and reapply contrast agents at least a few times in order to achieve a satisfactory C-arm angulation because pertinent details of the valve structure, such as the aortic root and coronary ostia are only visible for a short time period after application of a contrast agent. Specifically, after an initial angulation orientation, physicians capture fluoroscopic images and apply contrast agents to check if the orientation is satisfactory. If not, the C-arm system is rotated to a new position, thus necessitating reapplication of contrast agents.
Aside from angulation information, physicians may also require information regarding specific artificial valves used during surgery. For example, certain valves, e.g., Edwards Sapien valves, are preferably implanted slightly below the coronary ostia to avoid blocking blood flow to the coronary arteries. Similar to a human aortic valve, some artificial valves have three distinct pockets for valve leaflets. These pockets require proper alignment during implantation. Aortic valve landmarks, such as hinge points and commissure points may be used to provide guidance to physicians during implantation of an aortic valve.
Accordingly, a method for automatically detecting aortic valve landmarks in medical images is desirable.